Correlation Between Gel Structural Properties and Drug Release Pattern in Scleroglucan Matrices

Abstract

The drug delivery behavior of scleroglucan hydrogels was correlated with the structural features found by means of steady-state fluorescence studies. Theophylline at 0.4% in weight was used as the model drug and its release was measured using a Franz cell device. The results were fitted with a semi-empirical power law equation, finding significant differences between the 0.5% and higher than 0.8% scleroglucan concentrations (w/w). Four molecular fluorescent probes were used to test microenvironmental properties of the gel cavities, which will play a key role on the release of the pharmaceutical drugs. The results found by the fluorescence analysis are in good agreement with the ones obtained by release kinetics.